I think Rachmaninoff gave a good overview of the "game theory/strategy" of mission-stealing, its evolution, and its role in high level play in history.
The only thing I would add to that, from a theory/strategy point of view, is that I would emphasize the twin facts that:
- Romulans were clearly the "mission stealers" of the original design (Espionage against Kli/Fed, Immune to Espionage, and have the ships packing both the Range and Weapons to defend their territory, without attack restrictions).
- PAQ personnel (especially P, and especially Romulans) were notably light on skills, so meeting the mission requirements mission-stealing was a lot harder. This might have been partly due to game design, but it probably owed just as much (if not far more) to the fact that Decipher was constrained to only depict personnel and their skills based on what was seen on screen (or at least felt constrained to do so by their Paramount contract). We didn't see Romulans do much, so we didn't get Romulans who could do much.
These factors help prevent mission-stealing from being developed into as widespread a strategy as one might otherwise have expected, back in the day, since it was
hard, especially for more casual players.
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There are also more "social" reasons why mission-stealing didn't settle in to becoming a dominant or significant part of the meta, while also possibly explaining why Decipher felt it had to curbstomp it. Here are three such example reasons.
Reason 1: Deckbuilding is a huge part of the Star Trek CCG experience, but by its very nature, offers little in the way of instant gratification. You put a lot of energy into building a deck, but you don't get to feel good about it until you actually play it. The one exception (especially early in the game) may be designing, figuring out, or coming up with new or unexpected "combos." And the most frequent "combo" in Star Trek CCG is "dilemma combos." It feels good to solve the puzzle of coming up with a new, unseen, unexpected, or tricky dilemma combo, and you get that feeling even before you get to play it out in a real game (and of course the rush you get when actually using it and pulling it off is even greater).
Now imagine a world where people mission-steal frequently, so dilemmas are more evenly spread. It's hard to come up with 2-card dilemma combos, and some missions will have only 1 dilemma seeded by you. Suddenly, your decks no longer have 6 dilemma combos. They're lucky if they have any at all. So that "instant gratification" that came with deckbuilding isn't felt anymore, because you're not wasting time building combos you'll never use in a meta that doesn't support combos.
Players who like that gratification are going to feel pressure to "shame" mission-stealers, to keep that out of the meta, so they can preserve the aspect of the game they like (or rather, preserve the most enjoyable aspect of the game that is traditionally, otherwise, the least exciting).
Reason 2: Star Trek CCG's players are more inclined to be drawn in by the storytelling of the game than the "game" of the game. Back in the day, of all the major CCGs, Star Trek was by far the most story-driven. Most of us didn't choose to play Star Trek CCG back then because we loved games and thought that "Star Trek CCG" offered the best gameplay of the bunch. Rather, most of us chose to play Star Trek CCG because we loved Star Trek and the CCG let us play a game inside the world we loved. We were "Trek Fans" first and "Gamers" second.
And mission-stealing? Planning out which dilemmas to self-seed versus which to set up for us to walk through later? Bluffs and double-bluffs?
Those are more "gamey" elements, which are less interesting to a community that is less about the "CCG" and more about the "Star Trek" in "Star Trek CCG." Hell, dilemma combos are inherently more "storytelling" in their miniature three-act structure than the tactical element of scrambling for missions with only one mysterious obstacle underneath.
So the gamers who would have made "mission-stealing" a larger part of the meta probably weren't playing in the first place - if they were that kind of player, they were probably playing "Magic" or something. That left the more "storytelling" players to protect their sacred "Star Trek" at the expense of the "Game," again leading to a selection process against mission-stealing.
Reason 3: There are a lot of players (in lots of different games, not just "Star Trek CCG") that like things to be methodical, consistent, and expected. Routine. They don't like to be surprised or have their plans dashed out the window.
They're the kind of player that reads in the rulebook: "Typically, a player would place Dilemma cards under opponent's missions... but this is not the only strategy to follow." And they internalize the first part of that sentence for their first game, and don't bother with the second part of that sentence, or re-assessing as they get better at the game. Seeding dilemmas under your opponent's missions (and vice versa) is just
the way things should be and they get used to that.
And so then if you try to challenge that notion, they get upset.
It's the same story with any unexpected change against the routine. How many times do you get players complaining about <Latest Interactive Deck>? It's often the same people, with the same story:
"I've played <Latest Interactive Deck> several times and I can't beat it. Can we all just agree it's overpowered already, and finally ban <Latest Interactive Deck's Key Card>?"
Then you explain that <Latest Interactive Deck> is actually quite beatable, and there are several key strategies or cards you can use to counter it, evade it, or shut it down entirely. But then they react with horror, shock, and disdain, because that would mean using cards that would otherwise slow down their super lean solitaire mission-solver deck and you can't really expect them to do that now, can you?!?!
So they shame you and "look down" on you and call it "cheese" because they just don't want to actually step up and counter the deck or adapt their tried-and-true playstyle and strategy. If they can't beat it by doing what they always used to do, then it's "overpowered" and "winning at all costs" and "slimy."
And "Mission Stealing" was just an early-history example of <Latest Interactive Deck>, of which there have since been many more.
All of the above are examples of "social reasons" why mission-stealing didn't develop as a widespread strategy in a lot of (if not most or all) the different casual metas (though Rachmaninoff points out that at high-level play it was probably more prevalent). Which makes sense, since "social reasons" are naturally going to have less of an effect on hardcore gamers at the high level.
But because it doesn't develop in the casual meta, perhaps it becomes less important at the high-level than it otherwise would be.
More importantly, when you look at the players playing the game 25 years later, you see that a lot of ideas of what the game "should be" are holdovers from the domestic metas of years past, just as much (if not more so) than from the high-level meta of years past. And so you see the extreme reluctance to endorse such a strategy today (i.e., OTF).